Arcuate aeration tine

ABSTRACT

A soil aeration device may include a plurality of arcuate blades mounted to an assembly adapted to rotate and translate the blades proximate a ground surface, thereby forming aeration pockets in the soil. In certain embodiments, the arcuate tines penetrate and fracture the soil while minimizing the amount of soil lifted from the pocket deposited on the top of the soil. In various embodiments, a planetary gear assembly imparts to the tine a translational and rotational movement which creates a fractured pocket in the soil while minimizing the amount of soil lifted from the pocket and deposited on the surface of the soil. In still other embodiments, the arcuate tine may have mounted thereon a coring tube that cuts and removes a plug from the pocket formed in the soil.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.10/775,538 filed on Feb. 10, 2004 by David Maas et al., now U.S. Pat.No. 7,152,691 which is a continuation-in-part of U.S. patent applicationSer. No. 10/387,092 filed on Mar. 12, 2003 by David Maas et al., nowU.S. Pat. No. 7,096,968 which claims priority from U.S. ProvisionalApplication No. 60/363,786, filed on Mar. 12, 2002 by David Maas et al.,the entirety of which are incorporated by reference herein.

BACKGROUND

Soil aeration devices are generally designed to cut a plug out of thesoil instead of driving a spike into the soil because the latterapproach compacts the soil. Towable soil aerator devices typicallyremove plugs of soil while forming an enlarged soil aeration pocket.Such aerators include hollow cylindrical tubes that enter the soil at anangle to cut free a cylindrical soil plug which contains grass, grassroots and soil. As the soil aeration device moves forward, planetarygears in the soil aeration device cause the soil aeration tubes to pivotto form a soil aeration hole or pocket wherein the bottom portion of thesoil aeration hole is larger than the top opening of the soil aerationhole. The soil aeration tube is then lifted out of the soil to removethe soil plug, which is usually discarded on top of the soil.

One of the difficulties with soil aeration devices is that a substantialamount of soil, grass and roots in the form of cylindrical plugs areleft on top of the soil. These soil plugs must either be removed,allowed to decompose, or pulverized via mowing. Generally, the largerthe soil plugs, the longer it takes for the soil plugs to decomposenaturally.

DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective of a soil aerator device having a set ofaeration tines;

FIG. 2 is a top view of an aeration tine;

FIG. 3 is a side view of the aeration tine of FIG. 2;

FIG. 3 a is a front view of the aeration tine of FIG. 2;

FIG. 3 b is a back view of the aeration tine of FIG. 2;

FIG. 4 is a bottom view of the aeration tine of FIG. 2;

FIG. 5 is a partial side view showing the aeration tine of FIG. 2penetrating the soil;

FIG. 6 is a partial side view showing the aeration tine of FIG. 2partially rotated within the soil;

FIG. 7 is a partial side view showing the aeration tine of FIG. 2emerging from the soil;

FIG. 8 is a perspective view of an alternate aeration tine;

FIG. 9 is a top view of the aeration tine of FIG. 8;

FIG. 10 is an end view of the aeration tine of FIG. 8;

FIG. 11 is a side view of the aeration tine of FIG. 8;

FIG. 12 is a perspective view of yet another embodiment of an aerationtine;

FIG. 13 is a top view of the aeration tine of FIG. 12;

FIG. 14 is an end view of the aeration tine of FIG. 12;

FIG. 15 is a side view of the aeration tine of FIG. 12;

FIG. 16 is a perspective view of an aeration tine adapted for use onputting greens;

FIG. 17 is a top view of the aeration tine of FIG. 16;

FIG. 18 is an end view of the aeration tine of FIG. 16;

FIG. 19 is a side view of the aeration tine of FIG. 16;

FIG. 20 depicts a golf course green that has been aerated with theaeration tine of FIG. 16;

FIGS. 21-24 depict the planetary motion of arcuate tines in certainembodiments;

FIG. 25 is a top view of another embodiment of an aeration tine;

FIG. 26 is a side view of the aeration tine of FIG. 25;

FIG. 27 is a perspective view of yet another embodiment of an aerationtine;

FIG. 28 is a side view of the aeration tine of FIG. 27;

FIG. 29 is a cross-sectional view of the aeration tine of FIG. 27;

FIG. 30 is a partial side view of the aeration tine of FIG. 25penetrating the soil; and

FIG. 31 is a partial side view of the aeration tine of FIG. 25 emergingfrom the soil.

SUMMARY

A soil aeration device may include a plurality of arcuate blades mountedto an assembly adapted to rotate and translate the blades proximate aground surface, thereby forming aeration pockets in the soil. In certainembodiments, the arcuate tines penetrate and fracture the soil whileminimizing the amount of soil lifted from the pocket deposited on thetop of the soil. In various embodiments, a planetary gear assemblyimparts to the tine a translational and rotational movement whichcreates a fractured pocket in the soil while minimizing the amount ofsoil lifted from the pocket and deposited on the surface of the soil. Instill other embodiments, the arcuate tine may have mounted thereon acoring tube that cuts and removes a plug from the pocket formed in thesoil.

The apparatus described herein may provide one or more of the followingadvantages. In certain embodiments, the soil aeration device enables agrassy area such as a golf course fairway to be aerated without thedeposition of the plugs or significant amounts of soil on the grass,thereby permitting use of the fairway immediately after aeration withoutthe need to remove or mow soil plugs or otherwise treat the area. Insome embodiments, the translational and rotational movement imparted toan arcuate coring tine minimizes the size of the aperture cut in thesoil and the amount of soil lifted from the aeration pocket anddeposited on the surface of the ground.

The details of one or more embodiments are set forth in the accompanyingdrawings and the description below. Other features, objects, andadvantages of the invention will be apparent from the description anddrawings, and from the claims.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

FIG. 1 is a perspective view of a pull type soil aeration device 10having a frame 11 supported by a pair of wheels 12. A gear mechanism 13,which is connected to the power take off shaft of a tractor (not shown),rotates the tine holders 14 which contain a set of soil aeration tines15. In the embodiment shown the aeration tines are located on parallelmembers and rotate in an epicycle or planetary manner. A soil aerationdevice providing planetary motion is more fully described in Bjorge U.S.Pat. No. 5,469,922 titled Soil Aerator issued Nov. 28, 1995 and isincorporated herein by reference.

FIG. 2 shows a top view of soil aeration tine 15 capable of bothfracturing and removing soil. Soil aeration tine 15 comprises anelongated member 20 having a central axis 19. Elongated member 20 has afirst section 22 terminating in an apex end 23 and a second section ormounting end 21 for mounting elongated member 20 on a soil aerationdevice. Mounted to elongated member 20 is a cylindrical soil cuttingtube 25 which is positioned rearwardly or aft of apex end 23 so thatwhen apex end 23 of elongated member 20 is axially driven into a patchof soil the apex end 23 of elongated member 20 penetrates the patch ofsoil before the soil cutting tube 25 engages the soil. As the firstsection 22 penetrates the soil, it fractures the soil to form a partialsoil aeration pocket. Next, the soil 20 cutting tube 25 which ispositioned axially rearwardly of the apex 23 and has an annular cuttingedge 25 c and a conically tapered surface 25 a engages the soil aft ofthe apex end and proximate the soil aeration tine 15 to cut a plug ofthe soil free of the soil. Thus the fracturing of the soil occurs in thesoil around the lower portion of the hole and both fracturing and soilremoval occurs in the soil zone proximate the cutting tube which resultsin a soil aeration pocket in the soil where the soil aeration pocket islarger than the soil plug cut free of the soil and also without the soilcompaction that would occur if a spike were driven downward into thesoil.

FIG. 3 shows a side view of soil aeration tine 20 illustrating a portionof a divergent soil fracturing section 22 which includes an upwardlycurving soil fracturing face 20 a and an upwardly curving soilfracturing face 20 b that terminates at apex end 23. FIG. 3 a shows theopposite side of soil aeration tine 15 illustrating the other side ofthe divergent soil fracturing section 22 which includes identicalupwardly curving soil fracturing faces 20 c and 20 d that terminates atapex end 23. A soil lifting face 24 extends laterally from side-to sideof soil aeration tine 15. The soil lifting face 24 forms a scoop orspade so that when the soil aeration tine is rotationally removed fromthe soil the soil face 24 can lift or scoop soil from the soil aerationpocket.

The soil cutting tube 25 has a leading and annular cutting edge 25 cthat diverges outwardly along annular face 25 a to the cylindricalshaped soil cutting tube 25. The cutting edge 25 c of cutting tube 25 ispositioned a distance L rearward of the apex end 23 of soil aerationtine to enable the soil fracturing section 22 to penetrate and fracturethe soil before the soil aeration tube cuts a soil plug free of thesoil. In the embodiment shown the soil cutting tube is positioned atleast one and one half inches rearward of the apex end to ensure thatthe length of the soil plug is kept to a minimum. On the other hand thesoil cutting tube should extend sufficiently far along elongated member20 so as to ensure that one can cut through the top layer of grass andsoil. Thus, in the embodiment shown in the drawings the end of the tine15 lacks an end coring device.

FIG. 3 b shows a back view of soil aeration tine 15 with a first line 31extending outward from the central axis 19 of elongated member 20 and asecond line 30 extending outward from the geometric center of cuttingtube 25 with the distance between the centers indicated by the dimensionx. That is, FIG. 3 b illustrates that the cutting tube is laterallyoffset from the elongated member 20 so that cutting tube 20 andelongated member 20 enter the soil in a side by side condition.

FIG. 4 is a bottom view of soil aeration tine 15 illustrating that thesoil fracturing faces 20 a and 20 c extend axially along elongatedmember 20 and terminate at apex end 23. Thus the under side of aerationtine 15 presents soil fracturing surfaces 20 a and 20 c while the topside of soil aeration tine 15 presents the latterly offset andrearwardly positioned cutting tube 25 for cutting the soil to remove aplug of soil and grass.

FIG. 5 is a partial schematic illustrating how soil aeration tine 15penetrates a patch of soil 40 at an acute angle φ with respect to thetop soil. In the first step the soil aeration soil fracturing surfaces20 a, 20 b on one side of elongated member 20 and the soil fracturingsurfaces 20 c and 20 located on the opposite side of the elongatedmember penetrate the soil with the soil fracturing surfaces entering thesoil at an acute angle causing the soil 15 proximate the soil aerationtine 15 to fracture upward rather than compact. That is the acute anglepenetration of the soil fracturing surfaces with the fracturing surfacesfacing upward produces an upward component that forces the soil upward.As the soil can fracture and move upward the resistance to soilcompaction above the soil aeration tine 15 is less than the resistanceto soil compaction in the lateral direction. That is, lateral displacingsoil produces increased soil compaction since the soil must compactagainst itself. Thus avoiding direct lateral compaction inhibits soilcompaction. At the same tine the soil fracturing faces fracture theportion of the soil located ahead of the soil aeration tine the cuttingedge 25 c, which trails the apex end 23, cuts a soil plug free of thesoil. In the embodiment shown the cutting edge 25 c extendssubstantially perpendicular to soil aeration tine 15 to enable the soilaeration tube 25 to capture a soil plug aft of the apex end 23 as thesoil aeration tine 15 is driven axially into the soil. It should bepointed out that although multiple soil fracturing faces are shown it isenvisioned that only a single soil fracturing surface could be used.

FIG. 6 illustrates the step when the soil aeration tine is rotated in aclockwise direction as the tine is being moved forward. This rotationalaction results in an aeration pocket 41 being formed in the region firstpenetrated by the soil aeration tine.

FIG. 7 illustrates the further enlargement of the soil aeration pocket41 as the soil aeration tine 15 continues in a compound motion as aresult of the planetary action that drives the tine rearward during therotation of the support mechanism and forward due to the pulling of thesoil aeration device and the rotation of the aeration tine. As a result,the compound rotation causes the soil aeration tine top face 24 to liftor scoop soil from the aeration pocket while a cut soil plug 42 is heldin cutting tube 25 to be disposed of on the ground when the soilaeration tube 15 exits the soil. The result is that one can form a soilaeration pocket 41 with a minimum of soil compaction and a minimum ofdisplaced soil as the soil aeration tine with the aft cutting tuberemoves a soil plug of substantially smaller volume than a soil aerationtube located on an apex end of a soil aeration tube. Consequently, lesssoil is left on top of the soil since the soil plugs formed by thepresent method are smaller than soil plugs formed by the end coremethod. Yet at the same tine the aeration holes 41 formed in the soilare as large or larger than holes formed by a conventional cylindricalcutting tubes.

Thus the method of making a soil aeration hole 41 comprises the step ofextending an elongated member 20 having a lateral face 24 on one sideand a soil diverging section formed by races 20 and 20 c on the otherside into the soil to fracture the soil proximate the diverging faces.In addition, one cuts a soil plug free of the soil with the soilaeration tube 25 by cutting the soil plug from the soil located rearwardand lateral of the diverging faces 20 and 2 c. By rotationally removingthe elongated member 20 one can free the soil plug and form a soilaeration hole 41 having a top opening smaller than a bottom opening asshown in FIG. 7. Also by rotationally removing the elongated member 20with the apex end 23 and lifting surface 24 one can partially scoop outsoil with the soil lifting face 24 on the elongated member.

In the embodiments shown the soil cutting tube 25 has an externaldiameter larger than the external diameter of the aerator tine.Although, it is submitted that the diameter of the soil cutting tube 25can be governed by other factors such as soil types and soil conditions.

Thus the soil aerator tine 15 can include at least one soil fracturingface in a diverging section 22 which diverges in a direction rearwardfrom an apex end 23 on soil aerator tine 15 and in a direction away froma lifting face 24 on soil aerator tine 15. The soil aeration device 15illustrated in FIG. 3 a shows two soil fracturing faces 20 a and 20 csymmetrically positioned around a central axis 19 extending through thesoil aeration tine elongated member 20. A review of FIG. 3 a shows thatapex end 23 on soil aeration tube 22 is located lateral of the centralaxis 19 extending through the soil aeration tube 15. By having the soildiverging faces forming an off center apex 23 on one side of the soilaeration tine 15 the soil against the soil face 24 is penetrated withoutcompaction while the soil above the soil aeration fracture faces isforced away from the soil aeration tube. When the soil aeration tube isdriven at an acute angle into the soil the diverging fracturing surfacesmove the soil upward which fractures the soil without compacting thesoil.

FIGS. 8-11 depict an aeration blade 80 adapted for use in connectionwith the above-described aeration device 10. The blade 80 functionssimilarly to the aeration tine 15 discussed above, except that it doesnot cut and remove a plug of soil. The arcuate tine 80 penetrates thesoil as shown and described in connection with FIGS. 5-7, but becausethis blade lacks the soil cutting tube 25, no plug is removed from thesoil and deposited on the surface of the aerated turf. Rather, as theaeration tine 80 pivots in the motion shown in FIGS. 5-7, the arcuateend 81 of the aeration tine 80 cuts an aeration groove having a longerdimension in the direction of the cut, which provides a degree ofaeration comparable to that provided by aeration tine 15.

Moreover, turf aerated with tine 80 will not be littered with aerationplugs. As shown in FIG. 20, the surface 200 of the aerated turf remainssubstantially uniform. The aeration pockets 201 are visible, but nosignificant amount of soil has been deposited on the grass surface 200.Accordingly, the turf need not be further treated (as by mowing) beforereceiving approach shots or serving as a putting surface. The aerationtine 80 can thus be advantageously implemented to significantly reducemaintenance expenditures and virtually eliminate course downtime causedby aeration procedures. If the rotational velocity of the carrierholding the tine shafts is increased relative to the tractor land speed,the pockets will be located closer together. If desired, the pockets canoverlap one another so that each blade forms a continuous slit, as shownin FIG. 20. This same approach may be implemented with blades havingintegral coring tubes (described in further detail below) so that theholes made by the coring tube overlap. Such an implementation would forma relatively wide and continuous slit (approximately as wide as theaeration tube).

Returning to FIGS. 8-11, the aeration blade 80 has a tip 82, concaveedge 83, and convex edge 84. The cavity 85 is adapted to be receivedonto a mounting element (not shown) protruding from tine holders 14 ofthe soil aeration device 10. The blade 80 may be made of high strengthsteel, metal alloys, composites, hard polymeric materials, or othersuitable materials. The cavity 85 may include threads, keys, detents,cross-drilled tapped holes for set screws, or other suitable structurethat cooperates with the mounting elements on tine holders 14 tosecurely and releaseably hold blades 80. Releaseable mountingconfigurations advantageously facilitate removal of blades 80 forsharpening or replacement. The aeration tine 80 of FIGS. 8-11 has awidth 82 of approximately 7/16″.

The aeration tines of FIGS. 12-15 are similar to the tine of FIGS. 8-11,except that the tine of FIGS. 12-15 has a width 122 of approximately5/16″. The tine of FIGS. 16-19 has a width 162 of approximately ⅛″ andis adapted for aeration of surfaces which must remain particular flatand even after aeration, such as putting greens.

The operation of the arcuate aeration blades are shown in more detail inFIGS. 21-24. With reference to FIG. 21, an arcuate aeration blade 90penetrates soil 89 in a downward, clockwise motion 92. As the tractorproceeds in the direction shown by arrow 94, the planet gear (not shown)that drives the blade 90 rotates in clockwise direction (as shown byarrow 92) while being driven in a counterclockwise planetary direction(as indicated by arrow 91). As the tractor continues in the direction ofarrow 94, the blade 90 translates in the direction of arrow 91 whilecontinuing to rotate in the direction indicted by arrow 92, thus carvingan aeration pocket and causing soil fractures 93. Optionally, the blade90 can be mounted in the opposite direction, such that its longer bladeedge end faces in direction 94. Such an arrangement can be usefullyemployed to, for instance, lift soil from the aeration pocket, therebyincreasing the pocket's size.

FIGS. 23-24 depict an embodiment in which the planetary motion isreversed relative to that shown in FIGS. 21-22. The blade 98 plungesdownward into the soil 89 as it translates in the direction of arrow 96and rotates in a counter-clockwise direction, as indicated by arrow 97.As the tractor proceeds in the direction of arrow 95, the blade 98continues to translate and rotate in the aforementioned directions,thereby forming a pocket and soil fractures 99.

The blade 80 can be equipped with an aeration tube 25 on its trailing orleading edges as shown, for example, in FIGS. 25-26. In suchembodiments, the arcuate blade serves to fracture the soil which iscompacted by the soil aeration tube 25.

Referring to the embodiment shown in FIGS. 25-26, the aeration blade 80has a tip 82, concave edge 83, and convex edge 84 similar to thepreviously described embodiments. Mounting end 85 may include a cavity,threads, keys, detents, cross-drilled tapped holes for set screws, orthe like that cooperates with a mounting element (not shown) on tineholders 14 to securely and releasably hold blades 80. The aeration tube25 may be positioned on the trailing edge (e.g., convex edge 84) of theblade 80 and has a conically tapered surface 25 a that engages the soilproximate the aeration blade 80 to cut a soil plug and remove it fromthe ground (as shown in FIGS. 30-31). The aeration tube 25 is positioneda distance S rearward of the tip 82 to enable the blade portion topenetrate and fracture the soil before the aeration tube 25 cuts a soilplug free of the soil.

Referring to FIGS. 27-29, an aeration blade 180 includes an aerationtube 125 positioned along the convex edge 184 of the blade portion. Athreaded cavity 185 is formed at the proximal portion of the aerationblade 180 so as to cooperate with a mounting element (not shown) on tineholders 14 to securely and releaseably hold the blade 180. The aerationtube 125 is positioned a distance S rearward of the tip 182 to enablethe blade portion to penetrate and fracture the soil before the aerationtube 125 cuts a soil plug free of the soil. Turning to FIG. 29, thecentral axis of the aeration tube 125 is nonparallel to the central axisof the mounting end 85. The central axis of the aeration tube 125 issubstantially parallel with the tangent of the convex edge 184 to whichthe aeration tube 125 is coupled. Such a positioning of the aerationtube 125 facilitates efficient soil fracturing by the arcuate blade 180and soil cutting (e.g., cutting a soil plug) by the aeration tube 125.Similar to the embodiment shown and described in connection with FIGS.25-26, the aeration tube 125 has a conically tapered surface 125 a thatengages the soil proximate the aeration blade 180 to cut a soil plug asthe blade 180 penetrates the ground surface. As the arcuate blade 180cuts an aeration groove, the aeration tube 125 removes the soil plug ofsubstantially smaller volume in comparison to the end core method.

FIGS. 30-31 illustrate the manner in which the arcuate blade 80 and itsassociated aeration tube 25 (FIGS. 25-26) operate to fracture the soiland to cut a soil plug 42 from the ground. The aeration tube 25 ispositioned on the trailing edge (e.g., convex edge 84) of the arcuateblade 80 such that the tip portion 82 of the arcuate blade 80 contactsthe soil before the aeration tube 25. As shown in FIG. 30, the tractorproceeds in the direction shown by arrow 94, the planet gear (not shown)that drives the aeration blade 80 rotates in a clockwise direction(arrow 92) while being driven in a counterclockwise planetary direction(arrow 91). The aeration tube 25 mounted to the aeration blade 80 has aconically tapered surface 25 a that engages and cuts the soil proximatethe aeration blade 80 as the blade portion penetrates into the soil.Because the aeration tube 25 is rearward of the tip 82, the arcuateblade 80 penetrates and fractures the soil before the aeration tube 25cuts a soil plug 42 free of the soil.

In addition, the arcuate blade 80 may have a plowshare effect as itpenetrates into the ground surface. Whereas previous aerators haverequired considerable “head weight,” or ballast, to ensure that aerationdevice does not rise or lift when the aeration tubes impact the ground,the incidence angle of the arcuate blade 80 as it penetrates the groundsurface causes the blade to be drawn deeper into soil as the locomotiveforce from the tractor moves the aeration blade in direction 94. Theconcave configuration of edge 83 enhances the plowshare effect. Theplowshare effect tends to substantially mitigate or eliminate thetendency of the aerator 10 to lift off the soil as the aeration blades80 impact and enter the soil. This, in turn, lessens or eliminates theneed to add ballast or head weight to the aerator device to ensureproper operation.

Referring to FIG. 31, the tractor continues in the direction of arrow94, the arcuate blade 80 (and the attached aeration tube 25) translatein the direction of arrow 91 while continuing to rotate in the directionindicted by arrow 92. As such, an aeration pocket is formed by cuttingthe soil plug 42 using the aeration tube 25 and by fracturing the soilusing the arcuate blade 80. Because the aeration tube 25 is aft of tip82 the convex edge 84 can fracture the soil proximate the site of plugremoval so that the soil aeration pocket is formed with minimal soilcompaction and displacement. In many embodiments the aeration tube 25can be advantageously sized to remove a soil plug 42 of substantiallysmaller diameter than the plugs removed by conventional soil aerators.As a result, less soil is deposited on the turf surface. However, theaeration pockets formed in the soil have a significantly greater surfacearea and permit significantly improved circulation of air, water andnutrients because the soil in proximity to the pockets is fractured byoperation of the blade 80.

Certain of the aeration tines discussed herein may resemble a knife andhave the effect shattering the soil through which they pass.Accordingly, those aeration tines may generally be considered a type ofsoil-shattering knife.

Various additional modifications can be advantageously made to theapparatus described above in accordance with the teachings set forthherein. For instance, the edge on the concave side of the aeration blade80 can be replaced with a blunt surface. As noted above, the aerationblades tines can be oriented as shown in the figures, or they can berotated 180 degrees about the long axis of the blade. The planetary gearset can be modified to have any desired combination of clockwise andcounter-clockwise motions of the planet and sun gears so that, forinstance, both the translation and rotation of the blade are in aclockwise direction. The gear ratios and sizes can be freely modified tocreate pockets having different profiles and fractures. The tines can begrouped or staggered on the tine holders in any fashion desired. Forexample, the tines can be grouped in pairs or triplets along the tineholders. The tines can also be disposed at an angle relative to thevertical plane defined by the pocket shown in FIGS. 21-24 to accomplisha different type of soil fracturing.

Conventional cam driven (or plunger type) aeration devices using coringtubes may not typically be towed at speeds in excess of about 1 mile perhour. At speeds greater than that, the forward motion of the tractortends to cause the coring tube to tear through the soil in the forwarddirection before it can be lifted out of the coring hole.

In contrast, however the planetary system described herein can cooperatewith the arcuate shape of the aeration tine to form a leading pocketwhich provides clearance that enables the aerator to be towed atsignificantly higher speeds without tearing through the soil at theleading edge of the aeration pocket. As shown in FIG. 30, the aerationtine forms a leading pocket as the aeration tine penetrates the soil androtates in a clockwise direction away from the leading edge of thepocket. These two features separately and synergistically permit thetractor to be operated at higher speeds without the aeration tinetearing through the soil at the leading edge of the pocket. It should benoted that the rotational velocity of the carrier may be increased astractor speed increase to limit the duration of the tines' aerationsweeps. It has been observed that the planetary aeration system of FIG.30 can be towed at speeds of five, ten, or even twelve miles per hour inaccordance with the foregoing teachings.

A number of embodiments of the invention have been described.Nevertheless, it will be understood that various modifications may bemade without departing from the spirit and scope of the invention.

1. A soil aerator system comprising: a tine holder member; and at leastone aeration tine coupled to the tine holder member, the tinecomprising: a curved elongate member having a concave external surfaceand a substantially complementary and opposed convex surface, the curvedelongate member being operable to fracture soil and form an aerationpocket; and an aeration tube coupled to the curved elongate member atsaid convex surface so that the aeration tube is positioned laterallyaway from said convex surface opposite from said concave surface, theaeration tube being operable to remove a soil plug as the curvedelongate member fractures soil and forms an aeration pocket.
 2. Thesystem of claim 1, further comprising a gear assembly that impartsrotational and translational motion to the tine holder member.
 3. Thesystem of claim 2, wherein the gear assembly imparts a movement to theat least one aeration tine coupled to the tine holder member, saidmovement being adapted to form a slit in a soil surface and a pocketunder the soil surface which is larger than the slit.
 4. The system ofclaim 1, wherein the tine holder member is a shaft having means forretaining the at least one aeration tine.
 5. The system of claim 4,wherein the at least one aeration tine further comprises a threadedstructure positioned at a proximal portion of the elongated curvedmember, the threaded structure being releasably mountable to theretaining means of the shaft.
 6. The system of claim 1, wherein at leastone of the concave and convex surfaces include an edge adapted tofracture soil.
 7. A soil aerator system comprising: a tine holdermember; and at least one aeration tine coupled to the tine holdermember, the tine comprising: a curved elongate member having a concavesurface and a substantially complementary and opposed convex surface,the curved elongate member being operable to fracture soil and form anaeration pocket; and an aeration tube coupled to the curved elongatemember at one of said convex surface or said concave surface, theaeration tube being operable to remove a soil plug as the curvedelongate member fractures soil and forms an aeration pocket, wherein theconcave surface and the convex surface converge near a tip portion, theaeration tube being spaced apart from the tip portion.
 8. The system ofclaim 7, wherein the aeration tube is coupled to the convex surface. 9.The system of claim 8, wherein the aeration tube has a central axis thatis substantially parallel to a tangent of the convex surface proximatethe aeration tube.
 10. A soil aerator system comprising: a tine holdermember; a gear assembly that imparts rotational and translational motionto the tine holder member; and at least one aeration tine, the tinecomprising: means for fracturing soil and for drawing the aeration tineinto said soil, said means including a curved elongate member; and meansfor removing a soil plug, said plug removal means being coupled to thesoil fracturing means and being laterally offset from at least a portionof the soil fracturing means, wherein the soil fracturing meanspenetrates the soil before the plug removal means.
 11. The system ofclaim 10, wherein the plug removal means is operable to cut a soil plugwhile the soil fracturing means fractures soil to form an aerationpocket.
 12. The system of claim 10, wherein the fracturing and drawingmeans includes concave and convex edges, at least one of said edgesbeing adapted to fracture soil.
 13. The system of claim 12, wherein theconcave surface and the convex edges converge near a tip portion, theplug removal means being spaced apart from the tip portion.
 14. Thesystem of claim 10, wherein the gear assembly comprises a planetary gearassembly that imparts rotational and translational motion to the tineholder member.
 15. The system of claim 14, wherein the gear assemblyimparts a movement to the at least one aeration tine coupled to the tineholder member, said movement being adapted to form a slit in a soilsurface and a pocket under the soil surface which is larger than theslit.
 16. The system of claim 10, wherein the tine holder member is ashaft having means for retaining the at least one aeration tine.
 17. Thesystem of claim 16, wherein the at least one aeration tine farthercomprises means for mounting the curved elongate member to the retainingmeans of the shaft.
 18. A method of using a soil aerator system to forman aeration pocket, comprising: moving a soil aerator system over apatch of soil, the soil aerator system comprising at least one aerationtine coupled to a tine holder member, the aeration tine having a curvedknife portion and an aeration tube coupled to the curved knife portionand spaced apart from a tip portion; penetrating the patch of soil withthe tip portion of the aeration tine; fracturing the soil with thecurved knife portion; and removing a soil plug with the aeration tube.19. The method of claim 18, whereby an aeration pocket is formed in thepatch of soil, the pocket having a horizontal length significantlygreater than the diameter of the soil plug.
 20. The method of claim 18,farther comprising imparting rotational and translational motion to theaeration tine when the tine is at least partially in the soil such thatthe tine forms a slit in the soil surface and a pocket under the soilsurface.
 21. The method of claim 20, wherein the translational androtational movement is imparted by a gear assembly coupled to the tineholder member.
 22. The method of claim 18, wherein the knife portionincludes a convex edge and a complementary concave edge, the concave andconvex edges converging near the tip portion.
 23. The method of claim22, wherein the concave edge comprises a leading edge of the knifeportion as the soil is penetrated.